Comparable-store sales for the month of August at Wal-Mart, Target and Sears Roebuck missed analyst expectations.

The value-oriented retailers have been consistently posting better numbers than specialty and department stores as consumers continued to have concerns about the economy. This turn, however, signals deeper fears.

Monthly same-store, or comparable-store, sales are thought to be the most accurate measure of a retailer’s performance, as they track the year-on-year performance of stores open at least one year.

Sales at the Gap, which has posted same-store declines for the past 28 months, showed recovery, sliding a mere 2 percent.

“For the Gap, it seems like the worst is probably over,” J.P. Morgan retail analyst Brian Tunick said. “The hideous fashion-they won’t be making those same mistakes again.”

“Retail sales are definitely weighing down the market,” said Todd Salamone, director of research at Schaeffer’s Investment Research.

“The numbers weren’t pretty. Investors were hedging hopes that the consumer would be the savior, and with any inkling that the consumer is losing power, people tend to sell off stocks,” he said.

Though only one week into September, Salamone said not to expect any major changes for the rest of the month.

“September is a weak month. Stocks are being sold off, and the indicators are that it’s not the retail investor selling. People are concerned but they’re not doing much about it yet.” He added, “We haven’t seen all that can take place if people are scared.”

A top retail performer was Jos. A. Bank Clothiers, which racked up same-store sales increases of 15 percent for the month of August – perhaps signaling a return to a more tailored way of dressing after years of corporate casual.

“People keep talking about suits and [Jos. A. Bank has] suits,” said Michael Via, director of research at Anderson & Strudwick. “They also have sportswear and socks.”

And Jos. A. Bank is taking customers from other men’s clothiers.

“Every other men’s retailer was down, so they’re clearly taking market share from the others,” Via said. “They’re selling what people want to buy and the stores are in good locations.”

In other action, financial shares took a beating after news that Congressional investigators had requested leading investment bank Goldman Sachs and Credit Suisse First Boston to submit records of their work on initial public offerings for technology firms.

That inquiry is part of the investigation that has already put the Salomon Smith Barney unit of Citigroup under the microscope.